Various mobile devices, also referred to herein a User Equipment (UE), can operate in wireless communication networks that provide high-speed data and/or voice communications. The wireless communication networks can implement circuit-switched (CS) and/or packet-switched (PS) communication protocols to provide various services. For example, a UE can operate in accordance with one or more radio technologies such as: Universal Terrestrial Radio Access (UTRA), Evolved UTRA (E-UTRA), and Global System for Mobile Communications (GSM) as part of a Universal Mobile Telecommunication System (UMTS). Descriptions and specifications for UTRA, E-UTRA, GSM, UMTS and LTE (Long Term Evolution) protocols are available from the Third Generation Partnership Project (3GPP), which is a partnership that united telecommunications standards development organizations and provides their members with an environment to produce reports and specifications that define 3GPP technologies.
Evolved Packet Core (EPC) technology was developed based on the 3GPP core network architecture. In EPC, the user data and the signaling data are separated into the user plane and the control plane to allow a network operator to easily adapt and scale their networks. At a high level, EPC architecture includes four basic network elements: the Serving Gateway (SGW), the Packet Data Network Gateway (PDN GW or PGW), the Mobility Management Entity (MME), and the Home Subscriber Server (HSS). The EPC can be connected to external networks, which can include an IP Multimedia Core Network Subsystem (IMS).
An IMS is generally configured to facilitate the use of Internet protocol (IP) for packet communications, such as telephony, facsimile, email, Internet access, Web Service, Voice over IP (VoIP), instant messaging (IM), videoconference sessions, video on demand (VoD), and the like, over wired and/or wireless communication networks.
As discussed in more detail below, typical communication networks generally provide a single line or number that is associated with a UE. Various users can have several devices, each with its own line. In some cases, a user may wish to use one or more lines with one or more devices and/or share a line with other users. While some Over The Top applications may provide an ability for a user to use a second line on a device, such applications generally do not allow for multiple lines to be used on multiple devices in an efficient and/or transparent manner. Moreover, it is desirable to seamlessly switch between two different kinds of networks or different communication protocols during a phone call, e.g., between a Packet Switched Network and a Circuit Switched Network, but this can be difficult to accomplish in the context of multiple lines used on multiple devices. Accordingly, improved communications systems and methods are desired.
It will be appreciated that elements in the figures are illustrated for simplicity and clarity and have not necessarily been drawn to scale. For example, the dimensions of some of the elements in the figures may be exaggerated relative to other elements to help to improve understanding of illustrated embodiments of the present disclosure.